Re: [PATCH v12 1/8] drm/dp: Add support to indicate if sink supports AS SDP

[Nautiyal, Ankit K]

On 2/28/2024 8:08 PM, Mitul Golani wrote:

Add an API that indicates support for Adaptive Sync SDP in
the sink, which can be utilized by the rest of the DP programming.

--v1:
- Format commit message properly.

Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.gol...@intel.com>

LGTM.

Reviewed-by: Ankit Nautiyal <ankit.k.nauti...@intel.com>

---
  drivers/gpu/drm/display/drm_dp_helper.c | 25 +++++++++++++++++++++++++
  include/drm/display/drm_dp_helper.h     |  1 +
  2 files changed, 26 insertions(+)

diff --git a/drivers/gpu/drm/display/drm_dp_helper.c 
b/drivers/gpu/drm/display/drm_dp_helper.c
index 9ac52cf5d4d8..f94c04db7187 100644
--- a/drivers/gpu/drm/display/drm_dp_helper.c
+++ b/drivers/gpu/drm/display/drm_dp_helper.c
@@ -2913,6 +2913,31 @@ void drm_dp_vsc_sdp_log(struct drm_printer *p, const 
struct drm_dp_vsc_sdp *vsc)
  }
  EXPORT_SYMBOL(drm_dp_vsc_sdp_log);

+/**

+ * drm_dp_as_sdp_supported() - check if adaptive sync sdp is supported
+ * @aux: DisplayPort AUX channel
+ * @dpcd: DisplayPort configuration data
+ *
+ * Returns true if adaptive sync sdp is supported, else returns false
+ */
+bool drm_dp_as_sdp_supported(struct drm_dp_aux *aux, const u8 
dpcd[DP_RECEIVER_CAP_SIZE])
+{
+       u8 rx_feature;
+
+       if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_13)
+               return false;
+
+       if (drm_dp_dpcd_readb(aux, DP_DPRX_FEATURE_ENUMERATION_LIST_CONT_1,
+                             &rx_feature) != 1) {
+               drm_dbg_dp(aux->drm_dev,
+                          "Failed to read 
DP_DPRX_FEATURE_ENUMERATION_LIST_CONT_1\n");
+               return false;
+       }
+
+       return (rx_feature & DP_ADAPTIVE_SYNC_SDP_SUPPORTED);
+}
+EXPORT_SYMBOL(drm_dp_as_sdp_supported);
+
  /**
   * drm_dp_vsc_sdp_supported() - check if vsc sdp is supported
   * @aux: DisplayPort AUX channel
diff --git a/include/drm/display/drm_dp_helper.h 
b/include/drm/display/drm_dp_helper.h
index 0c1a4021e098..7c1aa3a703c8 100644
--- a/include/drm/display/drm_dp_helper.h
+++ b/include/drm/display/drm_dp_helper.h
@@ -101,6 +101,7 @@ struct drm_dp_vsc_sdp {
  void drm_dp_vsc_sdp_log(struct drm_printer *p, const struct drm_dp_vsc_sdp 
*vsc);

bool drm_dp_vsc_sdp_supported(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE]);

+bool drm_dp_as_sdp_supported(struct drm_dp_aux *aux, const u8 
dpcd[DP_RECEIVER_CAP_SIZE]);

int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]);